The year 1492 was an annus mirabilis for Spain. Granada was taken and the eight centuries of war with the Moslems brought to an end. The Jews were expelled from Spain, and the New World was discovered. Castile, which all through the Middle Ages had been secluded in the centre of the peninsula, suddenly emerged as a world Power. The rise of Castile was rather a matter of luck and accident than of thoughtful planning. But when opportunities came the Castilians rose to the occasion and seized them as successfully as they could, the chief limitation being the economic factor. Fate put enormous wealth into the hands of a nation with high ambitions and lofty ideals, but with little economic sense. No wonder the great empire which emerged was beset with financial problems. The real wonder is that it lasted so long.

The population in the peninsula under the Crown of Castile was not large. A count taken for military purposes in 1482 gave a total of 7,500,000. But the count was very rough and the figure seems much too high. Another count, taken in 1530 for tax purposes, gave only 3,433,000, but this did not include Galicia (perhaps with 600,000 people) or the kingdoms of Granada and Murcia, also densely populated. A third tax-count in 1541 gave about 6,272,000. Considering that 1530–70 was probably a peak period, the figure for 1482 ought to be much lower than for 1541, but should probably be over 4,500,000. As for the states of the Crown of Aragon, the approximate figures are: Aragon 270,000 (1495), Valencia 270,000 (1510) and Catalonia 307,000 (1512).